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 <textarea cols="30",row='10'>及哦即将过期哦及哦为契机科技金期我好好学习天天向上</textarea>
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<button class="btn" disabled >我已经ff阅读了(5)</button>
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  const btn =document.querySelector('.btn')
   let i=5
    const fn = setInterval(function(){
   i--
   btn.innerHTML=`我已经阅读了(${i})`
   if(i===0){
    clearInterval (fn)
    btn.disabled= false
   }
    
    
  },1000)

  
  
 </script>
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